Props...what to buy?

79nautique wrote: Oh and hire that out as it doesn't sound like your on top of your a game when it comes to tuning motors.

I appreciate your invitation but will respectfully decline you offer.

I came here to learn more about the boats I love and left other boards to get away from the personal attacks, name calling, and arguing.

Matt

Matt;

I came here to learn more about the boats I love and left other boards to get away from this type of thing.

This is not a slam on you nor your expertise, it is Chris and his way of inviting you to the site.
You will gain knowledge about these boats along with the differences between a "tractor" and "race car" engine.
Two entirely distinct concepts,dont wear your feeling on your sleeve and be prepared to learn.Or you will leave with out sharing with us what you have learned....
Lots of HOT MOTORS have been tried but few come up the BAR, glad your here to share................Boat dr

79, lets give him the benefit of the doubt here- he doesnt seem like he is overly familiar with Correct Crafts. A simple prop change may get him running just fine- and thats why he's asking the question. If a new prop doesnt result in an increase of 8+ mph, then we can start picking apart the tuning job.

79nautique wrote: Tim the prop isn't really going to make that big of a change to start with so it's the preverbial dog chasing the tail trick ignoring the obvious problem.

You might be right- lets wait and see. Ive heard of junk props doing weirder things.

1. Done. Can't fit .001 between the flanges.
2. Dwell does not matter with this set-up. The points are used as a trigger for the MSD (amplifier)...only. They only use about .1 volt in this configuration to trigger the MSD box. They simply act in a similar way to a magnetic or laser trigger. The coil does not charge through the points like a regular points set up. .1 volt vs 10-14 volts depending on wether or not a ballast resistor is used. As long as there is some contact the condition of the points is irrelevant.
3. Timing is set at 30 deg total (full advance). Experience with similar engines tells me it will like somewhere between 30-36 degrees.
4. Carb is spot on.
5. Will try 93 octane soon.

Magnetic or laser pick-up is better to trigger the MSD at higher rpm as points can still "bounce."

Here's why I think the prop is the problem:
30 mph at ~3,000 RPM
38 mph at ~5,000 RPM with noticable "slip"
Throttle response is very crisp.
Run 20 mph and nail it, boat nearly jumps out of the water. RPM's jump immmediately, boat plays catch up. Slip?
I can't hold the rope trying to get up skiing. My wife has to feather the throttle. I pulled a muscle in my arm trying. The torque is incredible.
There is a vibration between about 24-28 mph.
Plugs look great on mixture and heat range.
No miss, no ticking, no knocking, no smoke, no hesitation, clean plugs, heat range good, no plug fouling. Trans seems to work great at low rpm and fluid is spotless.

Don't worry, I'm not going to chase props. I would just like to try a known, good prop, and go from there. Looks like John (jbear) is going to help with the prop. Thanks!

I've focused my efforts on the race cars and spent little time tuning on the boat. Up to this point it was good enough for cruising and skiing on the weekends. Now that I've moved to the lake, I'd like to fix it up a little.

Thanks for your advice, it is well appreciated. We'll get this one figured out.

Matt

Brktracer wrote: There is a vibration between about 24-28 mph.

That's where your problem is...I think...or at least some of it. Your power delivery should be smoooth!

I have vibration at mid range also ('89 2001 with 1.23). Upon inspection last Fall, I saw that the shaft is not centered in the front end of the strut - about .015 inch off center by eyeball. The shaft also isn't centered in the 'log'. I am going to put in a new strut bushing & get everything lined up to the best of my ability. I hope I don't have to reset the strut alignment but will if that is what it takes.

BktRacer, let me know what you find out!

Chris

79 - Thanks, have done so & am looking forward to using the feeler gage. However, the strut bushing has the rubber crushed on one side & a gap to the shaft on the other. Doesn't seem right so I am going to replace that 1st & make sure everything is on center.

SNobsessed wrote: However, the strut bushing has the rubber crushed on one side & a gap to the shaft on the other.

Sounds like it may be bent a little...the shaft could be as well. I've read here somewhere that 'if you hit anything, something is bent'.

SNobsessed wrote: Buffalo - I can't see any damage but it is off center so far that I suspect something to be wrong.

Take a look at your engine mounts, they may be oviously skewed to one side. And I've had a prop with a bent blade that was only visable on the workbench and a strut that was about the same. I also wear glasses, so you may not want to listen to me at all?!!? LOL Seriously though, you may not have hit anything but someone else may have. When the prop and shaft assembly hit something...even lightly, part of the force is to the side.

Matt;

You've got mail.

john

PS; its on the way.

Matt, I know our boats are not the same but I had similar results. With an old 12x13 Michigan,3000 rpm would give me 32.5, 4000 was 40 and 4800 43.1
I then tried my old 12x 13 Federal , 3000 30.8, 4000 38.1 and 5000 was 41.8, I always thought something wasn't right,but there was no one to ask who knew what they were talking about until I found Keith's site and met these guy's who had actual experence with these boats. I then got a 12x14 Federal from a member here and what a difference. 3000 was 34.4, 4000 was 42.3 and 4200 was 45 but the biggest and best change was that the bow rode higher at speed. All props were tried on the same day and checked with gps.

No John went to the Chicago auto show.But I did say yes for Sunday and now I see the high for tommorow is 2.Dooh!

Hey TRBenj - I saw your advice on Acme 470 vs 1442 over on the 2001.com site. I forgot my password for that site so I am carrying it over here.

I'm going to buy one of these this spring.

I'm rock stock this year & going to stay that way until next year - the planned truck purchase will cash me out & so the GT40 heads will have to wait.

So my question is: Will the 1442 be OK with 240 HP? We wakeboard & wakesurf, my son just bought 2 fat sacks. Not so interested in top end, just want good midrange performance. Will a 1442 be any worse than the Federal 14x16 I now have?

Thanks for your advice

Chris

Thanks a bunch! 1442 it is.

It's great to get a recommendation form someone you trust & not just a salesperson.

The Federal is the original equipment - has a few nicks & I thought it would be a waste of money to have it rebuilt.

I can't wait for my shakedown cruise in April!

Chris